增強光動力殺菌物質CX的角色探討

Abstract

在先前本實驗室發現的一種之生醫材料compound X (簡稱CX)，合併於一種光感物質血紫質(Hematoprophyrin)之光動力殺菌，可以有效的增強光動力殺菌效果。本研究藉由將CX應用在其他種光感物質 Chlorin e6、Rose Bengal、Methylene Blue及Toluidine Blue O之光動力殺菌上，發現CX應用在這幾種不同帶電性及不同極性之光感物質對革蘭氏陽性菌金黃色葡萄球菌所造成的光動力殺菌都有增強殺菌的效果，顯示CX應用在不同種光感物質的光動力殺菌上之可行性。 再進一步了解使用微胞包埋脂溶性光感物質Chlorin e6 (PF127-Ce6)與free form Ce6，在與金黃色葡萄球菌培養不同時間或不同培養濃度的攝取量及光動力效應。結果顯示，不論是PF127-Ce6或是Free form Ce6，當光感物質與菌體在培養10分鐘之後光感物質的攝取量已達最大值；當與培養的光感物質濃度增強，攝取量也會隨之增高，光動力殺菌的效果也會跟著變強。一旦對革蘭氏陽性菌金黃色葡萄球菌的光動力殺菌效果達2 Logs以上，加入0.025% CX就可以增強殺菌效果達全殺。再更進一步研究探討，發現CX增強光動力殺菌也可應用於革蘭氏陰性菌綠膿桿菌及抗藥性金黃色葡萄球菌菌株，顯示CX應用於光動力殺菌上的潛力。 最後，在CX作用機制的研究上，針對CX不同的物理性質進行探討，發現不同濃度、不同分子量及不同去乙醯化程度之CX進行光動力殺菌後培養，發現增加CX濃度可增強光動力殺菌效果，而增強光動力殺菌效果和CX的分子量沒有明顯關係，但一旦CX的去乙醯化程度達85% 以上就有增強光動力殺菌之功效，顯示和CX增強光動力殺菌之機制和去乙醯化程度程度相關。

Previously, we have found that coincubation of compound X (CX) with Hematoprophyrin can enhance the photodynamic inactivation (PDI) effect against bacteria. In this study, we further investigate whether CX can also enhance the PDI efficacy mediated by other photosensitizers (PSs) in Gram positive as well as in Gram negative bacterium Staphylococcus aureus. We found that CX can also synergistically enhance the PDI antimicrobial effect mediated by Chlorin e6, Rose Bengal, Methylene Blue, and Toluidine Blue O with different charges and polarities. These results show the possibility of CX working in different PSs mediated PDI. Furthermore, we address the uptake and PDI effect by the hydrophobic PS, Chlorine 6 (Ce6) in its free form or encapsulated by micelle (PF127-Ce6) for different incubation times and concentrations in S. aureus. We found that the uptakes of free form Ce6 and PF127-Ce6 reached the maximum after 10 minutes incubation. Besides, the uptake and PDI efficacy is proportional to the concentration of Ce6. We found that if the PDI can exert more than 2 logs in bacterial killing, 0.025% CX can synergistically result in complete killing. Meanwhile, CX can also enhance the PDI effect in Gram negative bacteria such as Pseudomonas aeruginosa and Methicillin-resistant S. aureus (MRSA).